Storage rack assemblies have widespread use in warehouses, factories, and other industrial applications. Storage racks typically include a plurality of columns arranged in a grid pattern and interconnected by beams spanning between the columns. Typically, the columns are channel shaped in cross-section and have engaging holes arranged spaced longitudinally on a web portion of the channel shape. The engaging holes can be arranged in two vertical lines such that the ends of two beams arranged at the same elevation, but within adjacent bays, can connect to the web portion. The connection between columns and beams is explained, for example, in U.S. Pat. No. 5,131,781. Alternately, the engaging holes can be arranged spaced apart vertically in a single line along a center line of the web portion.
In the process of assembling storage racks for a warehouse, for example, the columns of a plurality of bays are assembled with the interconnecting beams to form an elongated, tall storage rack section. It is advantageous if the elongated storage rack section could be assembled at one location and then transported to its operating position. Thus, a single assembly station can be used to assemble racks rather than assembling each rack at its operating position. However, once assembled, the tall lattice of the storage rack section is somewhat unstable and heavy. In order to transport such storage rack within a warehouse it is known to employ a plurality of caster devices to lift columns of the storage rack and roll the storage rack section into its operational position, and then to remove the caster devices.
It is known to temporarily fix the caster devices to a bottom region of the columns of a storage rack section to provide for rolling the entire section into place. The caster assemblies each include a vertically arranged channel section for receiving the column and a single line of lugs within the channel section for engaging a single line of holes arranged along a web portion of the column. In these known assemblies, the lugs are parts of a connector permanently attached to the caster housing and, the caster assemblies are not interchangeable or adaptable between column styles.
It would be desirable to simplify the adaptation of caster assemblies to columns by providing a caster assembly which can be easily converted to engage either a single engagement hole-column column style to a double engagement hole-column style.